What is the maximum load weight required?  
Calculate load capacity:To calculate the load capacity of various castors ,the net weight of transported equipment,maximum load and number of monocastor or castor used must be provided.Load capacity required by a mmonocastor or castor is calculatyed as follows:X=(Y+Z)N/M;X=load capacity requipment;Y=Maximum load;M=number of monocastor or castor used;N=safety coefficient (about 1.3-1.5).
Is floor protection required?
  
What about noise reduction?Resilient tread wheels offer maximum noise reduction and floor protection.Hard tread sheels such as steel have high load capacity,but poor floor protection.Polyurethane tread wheels are a compromise,moderate floor protection with high load capacities.
What are the ambient conditions?
  
Check the environmental conditions for anything that could effect the operation of your caster and wheel.Verify the wheel type selected will operate in the temperature range of the application.Will he wheet type work if there are acids,oils chemicals,or grease?Do not forget the caster lubrication lubrication!Different types of lubricants are used depengding on the application requirements,such as hightemperarure grease(HTG)for ovens and low-temperature grease(LTG)for operatigntemperruture belows0.Refer to the wheel selection guide on page 8 for operating characteristics.
Rollability
The larger the diameter of the wheel,the easide it will roll.On smooth floors,the harder the tread,the easier the caster will roll.Resilient Resilient treade work best on rough floor surfaces,but can be difficult to move manually under heavy loads.Bearing selection will assist in the ease of rolling.Roller bearings carry heavier loads.Ball bearings roll easier with less carrying capacity.